Railroad tank car

ABSTRACT

A flexible diaphragm can be moved to line opposite surfaces of a tank vehicle so that incompatible fluids alternately can be transported in the vehicle without the need for cleaning it. The diaphragm is prevented from entering a manway on the vehicle, and an outage gauge is confined entirely within the manway to prevent damage to the diaphragm.

RELATED INVENTIONS

This application is a division of United States application for LettersPatent Ser. No. 932,817, filed Aug. 10, 1978, now U.S. Pat. No.4,210,254, which is assigned to the same assignee as this invention.

BACKGROUND OF THE INVENTION

This invention relates to wheeled vehicles, and more particularly torailroad tank cars for transporting different liquids in a givencontainer.

When a tank truck or a railroad tank car transporting a particular gasor liquid is to be used to transport a different non-compatible fluid,it is necessary to clean the container of the vehicle. This is usuallyexpensive and inconvenient, and the required specialized cleaningfacilities frequently are not available. To solve this problem, it hasbeen proposed that vehicles for transporting fluids be provided with apair of separate inlets and outlets and a flexible diaphragm thatalternately lines opposed sides of the vehicle's container. Movement ofthe diaphragm to line one side of the container provides a chamber forone fluid, and movement of the diaphragm to the opposite side of thecontainer provides a chamber for a different non-compatible fluid. Thus,the container does not have to be cleaned to enable the vehicle totransport either of such fluids. However, there has not been anysignificant use of such vehicles having a diaphragm that enables them toalternately carry non-compatible fluids without being cleaned inbetween. One reason such vehicles have not been used has been theextensive modification of standard vehicles believed necessary toprevent damage to the diaphragm or to the vehicle container orcomponents. For example, it is necessary that liquid transport vehicleshave a specified minimum empty space or outage in their upper end. Avisible gauge that projects into the vehicle tank has been used toidentify the uppermost permissible liquid level in the tank. Such agauge could not be used in a diaphragm vehicle because it could damage,or be damaged by, the diaphragm.

OBJECTIVES OF THE INVENTION

Accordingly it is an object of this invention to provide improved meansfor transporting non-compatible fluids.

Another object is to protect a flexible diaphragm from damage by thecomponents of a vehicle for transporting liquids.

Another object is to provide an outage sight gauge which cannot touch aflexible diaphragm that defines different liquid chambers in a transportvehicle.

Another object is to support a flexible diaphragm in a mansized hole ina liquid transporting vehicle.

Another object is to prevent an outage sight gauge from damaging aflexible diaphragm in a liquid transportation vehicle.

Another object is to provide a relatively inexpensive, durable, easilymaintained railroad tank car having a flexible diaphragm in itscontainer that does not possess defects found in similar prior art tankcars.

Other objects and advantages will be found in the specifications andclaims, and the scope of the invention will be pointed out in theclaims.

DESCRIPTION OF THE DRAWING

FIG. 1 is a schematic, partially broken-away side view of a railroadtank car in accord with this invention.

FIG. 2 is an enlarged partial top view of the car shown in FIG. 1.

FIG. 3 is a cross sectional view taken along the line 3--3 in FIG. 2.

DESCRIPTION OF THE INVENTION

The drawing shows a railroad tank car 1 including a metal tank 2 forcontaining and transporting alternately two different non-compatibleliquids, such as lube oil and diesel oil. Container tank 2 is generallycylindrical, and has a generally horizontal longitudinal axis; its endsare closed by dished heads 4. Tank 2 encloses a diaphragm 5 made from aflexible material having its terminal edge clamped at 6 or otherwisesealed against the inside surface of tank 2 around its entire peripheryin a generally vertical plane which generally bisects tank 2longitudinally. A pair of manways 7 and 8 are located adjacent the uppersurface of tank 2 on opposite sides of its longitudinal center, and apair of conventional liquid outlets 9 and 10 are located adjacent thelower surface of tank 2 on opposite sides of its longitudinal center. Apair of quick-fill nozzles 14 and 15 are also located adjacent the uppersurface of tank 2 on opposite sides of its longitudinal center. Nozzles14 and 15 and manways 7 and 8 provide pairs of upwardly extending liquidinlet conduits, each such pair providing an inlet conduit on each sideof the plane of the edge of diaphragm 5. Car 1 should be provided withother necessary conventional components and accessories, such as trucks,draft gear, ladders and platforms, which do not form part of the presentinvention.

When tank 2 is filled with a specific liquid through nozzle 14 or manway7, diaphragm 5 will lie against the inside wall surface of tank 2 anddefine a chamber for such liquid; such liquid would be drained throughoutlet 9. When tank 2 is filled with a non-compatible liquid throughnozzle 15 or manway 8, diaphragm 5 will be against the inside wallsurface of tank 2 and define a different chamber for the non-compatibleliquid; this liquid would be drained through outlet 10. The separatechambers for non-compatible liquids are hermetically isolated, so it isnot necessary to clean tank 2 whenever car 1 carries either of suchliquids.

Each manway 7 and 8 is made from an upstanding open-ended cylindricalring 17 welded to the upper portion of tank 2 around a man-sized hole 18through the tank. The rings 17 are located outside of and on oppositesides of the plane of the terminal edge of diaphragm 5. A manway coveror lid 20 is pivotally attached to each ring 17 by a hinge 21 forclosing the upper open end of the ring. Each lid 20 includes a vacuumrelief valve 22 and an air connection 23 of conventional design. Lids 20may be sealed against the top of rings 17 by nuts 25 threaded on to sixbolts 26 attached to hinges 27 on rings 17 and pivotable in conventionalmanner into slots 28 in lids 20. Conventional pressure relief valves 29are mounted on tank 2 adjacent the terminal edges of diaphragm 5.

Man-sized hole 18 defines a relatively large area (e.g. two sq. ft.) inwhich the inside wall of tank 2 cannot support diaphragm 5. Substantialgas or liquid pressures may occur in tank 2 which could force diaphragm5 through hole 18; this could force diaphragm 5 against components inone of the manways or against the edge of a hole 18 with sufficientforce to cut or tear the diaphragm. Baffle means such as plate 30 isshaped to conform to the curvature of the wall of tank 2. When lid 20 isclosed, baffle plate 30 is located in hole 18 so as to defineessentially a continuation of the inside surface of the tank wall thatprovides means for supporting diaphragm 5 and thereby preventing thediaphragm from being forced through hole 18 by pressure in the tank. Acylindrical tubular member 31 extends through ring 17 and has its upperend 32 attached to the underside of lid 20. The lower end 33 of tubularmember 31 is attached to the center portion of baffle 30. One or morevent holes 35 are provided in tube 31 at end 33 to permit drainage ofliquid or condensation. The annular space 36 separating the edge ofbaffle 30 from the edge of hole 18 is sufficient to permit lid 20 toswing open without baffle 30 binding against ring 17 but is insufficientto permit diaphragm 5 to enter hole 18.

The vertically lowermost portion or edge 37 of each ring 17 is spacedbelow the top surface of tank 2 a predetermined vertical distance (e.g.four inches) sufficient to define adequate outage space in the top ofthe chamber on each side of diaphragm 5 for the liquid tank 2. An outagesight gauge 38 is located entirely within each ring 17 adjacent edge 37.Gauge 38 may be a brightly colored metal bar or other object that isvisible in a manway when in contact with a liquid, and no part of gauge38 need project below hole 18. Baffle 30 prevents diaphragm 5 fromentering hole 18, so the diaphragm cannot contact gauge 38.

When the chamber defined by one side of diaphragm 5 is filled withliquid, it is necessary that the chamber defined by the other side ofthe diaphragm be vented to the atmosphere. This permits escape of air orvapor from the vented chamber as diaphragm 5 moves against the insidewall surface of tank 2 that had previously defined such vented chamber.Each of manways 7 and 8 may have a vent line 39 connecting a vent port(not shown) on the inside of its ring 17 to a vertical vent pipe at 41.Thus, the chambers on both sides of diaphragm 5 may be vented to theatmosphere whenever either chamber is filled through a manway.

It has thus been shown that by the practice of this invention extensivemodification of a railroad tank car 1 is not necessary to permit use ofa flexible diaphragm 5 for providing separate chambers fornon-compatible fluids. A baffle plate 30 in each of manways 7 and 8prevents excess pressure or pressure surges from forcing the diaphragmthrough hole 18, and the location of the lower edge 37 of each manwayfar enough below the top surface of tank 2 permits the outage sightgauge 38 to be confined entirely within each ring 17 where the diaphragmcannot touch them.

While the present invention has been described with reference to aparticular embodiment, it is not intended to illustrate or describeherein all of the equivalent forms or ramifications thereof. Also, thewords used are words of description rather than limitation, and variouschanges may be made without departing from the spirit or scope of theinvention disclosed therein. It is intended that the appended claimscover all such changes as fall within the true spirit and scope of theinvention.

What is claimed is:
 1. A wheeled vehicle for transporting a plurality ofnon-compatible liquids, comprising:A. a container for such liquidscomprising a generally cylindrical tank having a generally horizontallongitudinal axis; B. a flexible diaphragm in said tank, the peripheryof said diaphragm contacting the wall of said tank in a generallyvertical plane which generally bisects said tank, said diaphragmalternately lying against opposite portions of said tank so as to definedifferent chambers for such non-compatible liquids; C. means for sealingsaid diaphragm against said wall; and D. A separate manway for each ofsaid chambers, each manway comprising:1. a generally circular open-endedring attached to said tank around a man-sized hole through said wall,said ring being located entirely outside of said plane;
 2. a movable lidclosing said open end of said ring, said lid being pivotally attached atone end to said ring; and
 3. baffle means attached to and movable withsaid pivoted lid and extending downwardly therefrom through said ringinto said man-sized hole for supporting said diaphragm and therebypreventing said diaphragm from being forced up into said man-sized holeby pressure in said tank.
 2. The invention defined in claim 1, whereinsaid baffle means is located in said man-sized hole and has its edgeseparated from the edge of said man-sized hole by an annular spacesufficient to permit said lid to pivot open without causing said bafflemeans to bind against said ring, and said annular space beinginsufficient to permit said diaphragm to enter said man-sized hole. 3.The invention defined in claim 2, wherein said baffle means comprises aplate shaped to conform to the curvature of said tank wall, said baffleplate being located in said hole to define essentially a continuation ofthe inside surface of said tank wall when said lid is closed.
 4. Theinvention defined in claim 2, wherein said baffle means is attached tosaid lid by a tubular member extending through said ring.
 5. Theinvention defined in claim 4, wherein the upper end of said tubularmember is attached to the underside of said lid, and the lower end ofsaid tubular member is attached to the center portion of said bafflemeans.
 6. The invention defined in claim 5, wherein said tubular memberhas a vent hole adjacent its lower most edge for drainage of liquid andcondensation from the inside of said tubular member into said container.7. The invention defined in claim 6, further comprising an outage gaugelocated entirely within said ring adjacent the lowest portion of saidring, said gauge being visible from said manway when in contact withsaid liquid without ever being contacted by said diaphragm.
 8. Arailroad tank car for transporting a plurality of non-compatibleliquids, comprising:A. a container for such liquids comprising agenerally cylindrical tank having a generally horizontal longitudinalaxis; B. a flexible diaphragm in said tank, the periphery of saiddiaphragm contacting the wall of said tank in a generally vertical planewhich generally bisects said tank, said diaphragm alternately lyingagainst opposite portions of said tank so as to define differentchambers for such noncompatible liquids; C. means for sealing saiddiaphragm against said wall; and D. a separate manway for each of saidchambers, each manway comprising:
 1. a cylindrical open-ended ringattached to said tank around a man-sized hole through said wall, saidring being located entirely outside of said plane;2. a lid pivotablyattached to said ring for closing said open end of said ring; and 3.means in said man-sized hole for supporting said diaphragm and therebypreventing said diaphragm from being forced up into said man-sized holeby pressure in said tank comprising:a. a cylindrical tube extendingdownwardly through said ring and having one end attached to the centerportion of the underside of said lid; b. a baffle plate attached to theother end of said tube and occupying said hole when said lid is closed,said baffle plate being shaped to conform to the curvature of said tankwall and defining essentially a continuation of the inside surface ofsaid tank wall, there being an annular space separating the edge of saidbaffle plate from the edge of said man-sized hole, said annular spacebeing sufficient to permit said lid to pivot open without causing saidbaffle plate to bind against said ring, and said annular space beinginsufficient to permit said diaphragm to enter said man-sized hole. 9.The invention defined in claim 8, further comprising an outage gaugelocated in said annular space between said baffle plate and the lowestportion of said ring entirely within said ring, said gauge being visiblefrom said manway when in contact with said liquid without ever beingcontacted by said diaphragm.